Spindle snugging pirn



Sept. 16, 1969 cc. LALLEMAND SPINDLE SNUGGING PIRN Filed July 7, 196'? INVENTOR. Charles C. LAllemund M, M W x ATTORNEYS United States Patent US. Cl. 242--46.21 7 Claims ABSTRACT OF THE DISCLOSURE A spindle snugging pirn is provided for minimizing vibration when used with dog drive spindles in which the pirn-centering section of the spindle is below the driving connection, resilient gripping fingers being formed in the centering section of the pirn for engagement with the pirn centering section.

This invention relates to textile bobbins, and more particularly to draw twister tubes or pirns.

Prior LAllernand application, Ser. No. 623,386, filed Mar. 15, 1967, for Plrn With Spindle Snugging Mounting discloses a pirn structure for minimizing the effects of drive end clearance, by providing resilient gripping means on the pirn for engaging the spindle base. The present invention is directed to an improvement thereon, in which the pirn is seated on a spindle in which the centering section is surmounted by the dogs or other drive means, requiring the positioning of the resilient elements below the drive lug socket elements of the pirn. It is an object of the invention to provide a drive end structure of this type, in which the resilient elements are positioned in the centering section itself. A further object is to provide an arrangement of this type in which the resilient elements have the form of upwardly extending tongues, and in which the structure is adapted to forming by a molding operation.

With the foregoing objects in mind, as well as others which may appear in the course of the following description, a preferred embodiment of the invention will now first be fully described with reference to the accompanying drawing, and the features forming the invention will then be pointed out in the appended claims.

In the drawing:

FIG. 1 is a somewhat schematic elevation of the pirn of the invention, showing also part of a spindle carrying the same;

FIG. 2 is a vertical axial section of the drive end fitting, taken on the line 22 of FIG. 3, the spindle being shown in elevation in the left half of the view and being omitted in the right half thereof;

FIG. 3 is a view, partly in plan and partly in horizontal section, on the line 33 of FIG. 2; and

FIG. 4 is a bottom view of the end fitting of FIGS. 2 and 3.

While the invention is applicable to pirns generally, without restriction as to size, it can be assumed, by way of illustration, that the pirn diameter is about two inches or somewhat less, so that FIG. 1 is somewhat reduced and FIGS. 2, 3 and 4 are much enlarged.

The pirn 1 is shown as seated on the whorl 2 of a spindle. The pirn barrel 3 has an upper bearing element 4 which fits the tip of the spindle blade 5, and a lower or drive end fitting 6. The drive end fitting 6 is formed with a lower centering section 7 which fits around the spindle base section 8 at the base of the spindle blade and with a drive socket section 9 which engages the drive lug or dogs 10 of the spindle. The present invention is concerned primarily with the drive end structure and the combination of the pirn and spindle. The structure of the pirn generally Patented Sept. 16., 1969 ice forms, in itself, no part of the present invention, and reference may be made to the above-mentioned application for the details of such structure.

The spindle itself is of a known type in which the whorl 2 supports the pirn (drive end fitting 6 sitting on the whorl, as indicated), and the spindle base section 8, intermediate in diameter between the whorl and spindle blade 5, projects up from the whorl and carries the drive lug means or dogs 10.

The pirn drive end 6 comprises a tubular outer portion which has an upper rim 11 and annular base 12, which seats on the whorl. A shoulder 13 is provided to seat the lower end of the barrel (the inside surface of which is indicated by the dot-dash lines 14), as in the above-men tioned application, and the rim 11 (suitably reinforced, as required), is force fitted or otherwise secured in the pirn barrel. The barrel may have an outer cover which overlaps the end fitting below the shoulder 13.

The pirn drive end 6 is preferably formed of plastic (synthetic resin) such as nylon or ABS resin (e.g. Kralastic) by molding. While it is an advantage of the present invention that it permits this method of manufacture, the invention in its broader aspect is consistent with the use of still other materials, including steel or other metals, for constructing the drive end or parts thereof.

The annular base 12 of the drive end joins an inner tubular section which forms the pirn centering section 7, previously referred to, and surrounds the spindle base sec tion 8. The inner surface of the pirn centering section 7 and the outer surface of the spindle base section 8 are spaced radially apart a predetermined distance so as to provide radial clearance between these parts. The tubular centering section 7 extends up slightly above the top of the spindle base section 8 and connects to the intermediate annular section 15, which supports, in turn the collar 16. Enlargements 17 to each side of the collar 16 form the sockets 9 for receiving and forming a drive connection with the dogs 10. Collar 16, generally, is spaced from the spindle blade 5, and it serves primarily to stiffen and strengthen the structure.

U-shaped apertures 18, 19 in the outer edge of the annular portion 15 and centering section 7 form tongues 20 in the wall of section 7 for engaging against the spindle base section 8. Each tongue 20 has an upper end 21 which projects inwardly of the profile of the inner surface of section 7, preferably by an amount which is several times the radial clearance between centering section 7, generally, and base section 8. Thus, if a clearance of 0.002" radially is provided for (or a range from 0.001 to 0.003), a projection of the tongues inwardly by 0.007" would be suitable. In any event, the extent of projection of the tongues 20, considering also the characteristics of the material of which they are formed, their shape, and any other factors affecting their elasticity or stiffness, will be selected so as to center the drive end with reference to section 8 of the spindle and to damp out any vibration which may occur, while avoiding any objectionable resistance to placement and removal of the pirn. In FIG. 4 and FIG. 2 (right) the tongues 20 are shown in relaxed (radially inward) position; while FIG. 3 and FIG. 2 (left) show them as forced back and stressed by engagement with the spindle base section 8.

The resilient gripping action provides a frictional resistance to rotative movement of the pirn relative to the spindle and a resilient and frictional resistance to lateral displacement, effectively minimizing the effects of clearance between the pirn drive end and spindle. The loading of the spindle supporting bearings is accordingly reduced to an acceptable level and hammering action due to sudden impact is substantially eliminated. Significant increases in permissible operating speeds and in length of spindle and spindle bearing elements may therefore be obtained.

What is claimed is:

1. In a draw twister machine, and in combination, (a) a spindle having a cylindrical base section for centering a pim on the spindle and drive lug means above said base section for driving said pirn with the spindle, and (b) a pim having a drive end structure comprising a pirn centering section fitting around said spindle base section and socket means receiving said drive lug means and I- tatively coupling the pirn to the spindle, said centering section and said base section having a radial clearance therebetween, the wall of the centering section having apertures formed therein, said apertures defining upwardly extending spring tongues engaging said base section, said tongues projecting radially inwardly of the centering section wall, when removed from the spindle, by an amount exceeding the radial clearance between the pirn centering section and the spindle base section, whereby said tongues are stressed by engagement with said base section, gripping the same resiliently to oppose rotative and lateral movement, thereby absorbing impact and damping vibration.

2. The combination according to claim 1, in which the inward projection of said spring tongues is several times the radial clearance between said centering section and said spindle base section.

3. The combination according to claim 1, comprising an intermediate annular section supporting said socket means from the centering section wall between said apertures, thereby holding the upper edge of said wall in position and transmitting driving and braking torque between spindle and pirn therethrough.

4. A pirn for use on spindles having concentric base sections surmounted by drive lug means, for respectively centering and rotatively coupling a pirn, and comprising a drive end structure having a tubular centering portion for fitting around a spindle base section, U-shaped apertures in the wall of said centering portion defining upwardly extending tongues, the said tongues extending radially inwardly of the inner surface of said centering portion so as to be pressed radially outward by engagement with a said spindle base section so as to grip the same resiliently, resisting movement from centered position, absorbing impact and damping vibration.

5. A pirn according to claim 4, comprising socket means for receiving the drive lug means of the spindle and an annular support mounting said socket means on the upper edge of the centering section wall between the apertures.

6. A pirn according to claim 4, in which the inner surface of the wall of the tubular centering portion and the outer surface of the spindle base section are separated by a predetermined radial clearance, and in which the tongues project radially inwardly of the centering section wall by several times the designed clearance between the said wall and the spindle base section.

7. A pim according to claim 6, in which said inward projection of the tongues is substantially 0.007.

References Cited UNITED STATES PATENTS 51,340 12/1865 Murdock 242-46.12 1,972,784 9/1934 Magrath 242-4621 2,262,787 11/1941 Anderson 242--46.21 2,377,920 6/1945 Atwood 242118.31 2,625,335 1/1953 Atwood 242-46.21 2,953,317 9/1960 Atwood et a1. 242-4621 X STANLEY N. GILREATH, Primary Examiner 

